Magnetic material and process of making the same



Patented June 12, 1934 I UNITED STATES PATENT OFFICE Edward M. Davidson,New York, N. Y.

No Drawing. Applicatio n April 3, 1925, Serial No.

20,426. Renewed November 4, 1933 3 Claims.

The object of this invention is to provide a method or process by whichI produce a new.

material or composition of matter having peculiar magnetic and otherproperties not heretofore possessed by any known material, so far as Iam aware.

The novel magnetic properties or characteristics are strikingly shownwhen a piece of the material is brought within a magnetic field, asadjacent one pole of a magnet. The first effect is an attraction andmovement of the piece of material towards the magnet pole, as in thecase of any magnetic material; but, as the end of the piece of materialreaches the magnet pole, or adjacent one edge thereof, instead ofstopping and being held against the pole, as would be the case withordinary magnetic material, it continues to move past the pole, whichapparently exerts a repelling action on that part of the piece ofmaterial which first approached or was adjacent the magnet pole.

I do not attempt to account for this perculiar property of the material,which apparently possesses the property of changing its characteristicsin a magnetic field when approaching and reaching the maximum intensityof the magnetic field to which it is subjected. I

In the preparation of this material, I take rock or stone containingsilica, alumina, lime and magnesia. This is ground and treated withsulphuric acid, sufficient acid being used to form a paste.

I then take a magnetic material, such as ma netic oxide of iron(magnetite) and treat with sufiicient sulphuric acid to form a paste,which paste is added to and mixed with the rock paste above described,and then the following ingredients added iheretoz-phosphorus, whitearsenic and tungsten metal.

The heavy paste thus formed is then shaped into bricks or other formsuitable for smelting and melted in a suitable smelting furnace and runinto moulds of any desired form.

An analysis of the material thus produced shows that it is composed ofthe followingz-silica, 33%; alumina, 6%; lime, 2%; magnesia, .'75%;ferric oxide, 56%; phosphorous, .06%; sulphur, .01%; arsenic, .5%;tungsten, 1.5%.

The material hardens when cooled and becomes extremely hard and tough,which properties render it useful for many purposes, in addition toits'utility in connection with a source of motive power and electricallyor magnetically operated mechanisms, etc., on account of its peculiarmagnetic properties, heretofore described.

It will be understood that the specific example of materials and methodused in the preparation of this novel magnetic material are those whichI have found to be desirable and'which will produce the results desiredunderstood as limiting myself to such particular materials or method, asI believe it may be possible to vary the same without departing from thespirit of the invention as defined in the appended claims.

What I claim as new and desire to secure by Letters Patent is:-

1. The process of making a composition of matter, which comprisesgrinding together silica, alumina, lime and magnesia and treating withsufficient sulphuric acid to form a paste, forming a second paste ofmagnetic material and sulphuric acid, mixing the two pastes together andadding phosphorus, white arsenic and tungsten thereto, mixing, smeltingand cooling sultant composition, thereby forming a hard material capableof changing its magnetic characteristics while under the influence ofthe same magnetic field.

2. The process of making a matter, which comprises grinding togethersilica, alumina, lime and magnesia and treating with sufficientsulphuric acid to form a paste, forming a second paste of magnetic oxideof iron and sulphuric acid, mixing the adding phosphorous, white arsenicand tungsten thereto, mixing, smelting and cooling the resultantcomposition.

3. A material or composition of matter capable but I do not wish to be60 the recomposition of two pastes together and of changing its magneticcharacteristics while 0 under the influence of the same magnetic field,comprising over fifty percent of ferric oxide, over forty percent ofsilica, alumina, lime and magnesia, and a smaller proportion ofphosphorous, 5

sulphur, arsenic and tungsten.

EDWARD M. DAVIDSON.

